-LRB- CNN -RRB- -- Wednesday night 's debate showcased a Mitt Romney resisting his worst debating weaknesses and playing solidly to his strengths . Barack Obama ? This time , he could n't overcome a weakness he has shown before , a tendency to distance himself from the audience , and this kept him from connecting and making a good showing .

But both have a track record of debates showcasing their strengths and weaknesses , and they are both good debaters . This is only the first of three performances . Many of their old habits emerged again , both good and bad . They will need to study their take-home lessons .

Let 's begin with Romney .

Three of of Romney 's debating strengths are being smooth and knowledgeable and having excellent first-line answers to questions . Wednesday night ?

Opinion : Romney was hungry , Obama was flat

Check . Check . And check .

Listen , Mitt Romney can handle these debates . He was strong in all areas Wednesday night . And y' all should n't be surprised that he performed so well . For him to falter , the moderator is going to have to do a much better job than Jim Lehrer . Poor , steamrolled Jim Lehrer . Romney talked over him so often that I swear one time I saw Lehrer slumping behind his desk while he meekly gazed up at Romney and muttered , `` Excuse me , I believe you have my stapler . ''

Romney has potential weaknesses : This smoothness has sometimes gotten in his way , which is how he got the `` Slick Mitt '' moniker . But he corrected the potential error and instead had a solid , conversational manner in the debate . He was believable .

Romney 's other potential weakness is where he shined the most . In the Republican primaries , Romney was n't a great debater when he was trailing in the polls . But not Wednesday night . He debated to win instead of `` not to lose '' -LRB- which is what Obama did -RRB- . Romney put Obama on the defensive and kept him there all night defending his policies .

Romney stuck to his theme of too much government overstretch during the Obama administration , whether on energy subsidies , health care , taxes or increasing the deficit . He kept the debate on the economy and jobs while flatly stating that it was overreach of federal government power that was what has inhibited our economy from recovering . And he made the point well .

Opinion : Romney shakes up the race

As for Obama , one strength is that he is solid at picking a theme and sticking with it . Wednesday night was no different . But what a difference four years makes . Against John McCain in 2008 , Obama focused on the economy as his theme and hammered away at George W. Bush and McCain . This time , Obama clearly presented his theme . The problem was that the new premise lacked bite . What was it ? That Romney has no specific plan .

Obama mentioned this time and time again : taxes , deficit reduction , entitlements , regulations to Wall Street and health care . Romney has not specified the details of how he will govern in all these important areas . The problem was that Obama needed to couple that theme with something else . Just stating it over and over is hardly a scathing indictment . And it failed to put Romney on the defensive .

Reasoning is another strength Obama has shown in previous debates , but he was unable to use it in any significant way . Near the beginning of the debate , he mentioned that arithmetic proved Romney 's plans unworkable . While I thought this was an excellent point , it should have been much more forceful .

Which brings us to Obama 's weaknesses : I wrote two days ago that his detachment was one weakness , that he can appear dispassionate and distancing to the audience . Unfortunately for the president , he did n't correct this . In fact , it was worse . Indeed , this was probably his poorest showing at trying to connect with the American people .

Being emotionless can work either for or against you . For Obama , with a troubled economy , it works against the president . If our economy is n't fully recovered and we 're in hard times , our president should at least show more empathy . Offer strong examples to show that he understands . Couple that with Obama 's failure to tie Romney to anything related to the famous 47 % comment , and I 'd call it a glaring error in the debate .

Opinion : It was n't just Romney who won

You know it 's bad when at the end of the debate , uber-wealthy Mitt Romney seems like he cares more about the middle class and even the lower class than the sitting Democratic president of the United States .

Both candidates get almost two weeks off before their next debate . Here 's what they each need to do in the meantime in their preparation .

Obama needs to find a much more effective way to pin Romney down to a specific policy . Although he is correct that some of Romney 's numbers simply do n't add up , Obama must do a better job of wrestling the details out of him . He simply has to put Romney on the defensive more often and provide arguments -LRB- and passion -RRB- that will resonate with voters . He ca n't let opportunities slip by to tie Romney to the 47 % comment or even to the old policies of George W.Bush .

This will be no easy task , since Romney was able to fend off most criticisms with ease in his many Republican primary debates . Obama will need to stick to one subject over a series of exchanges . If he does n't , Romney will be like Teflon , and nothing Obama says will stick to him in these debates .

And the president should utilize the backward-step-pivot-forward technique as often as possible . Since Romney will continue to put him on the defensive -LRB- and this is guaranteed -RRB- , Obama must turn potential flaws into strengths . It 's easy enough to predict Romney 's attacks . Now , the president must figure out rhetorically how to turn those criticisms into benefits .

Opinion : Romney was n't stellar , but Obama fell short

And for goodness sake , Obama , show more energy and passion . Speak with conviction .

For Romney : Steady as she goes . He needs to keep debating precisely like Wednesday night . It was n't a fluke , and he can prove it . Romney was assertive -LRB- compared with Obama 's passivity -RRB- . And it worked .

But there 's a fine line between assertiveness and aggression . Romney was assertive in this debate without being aggressive . If he decides that his bullying technique of the moderator was effective -LRB- it worked Wednesday night , but I would n't push my luck if I were him -RRB- , then he risks alienating voters .

The same is true with his demeanor toward the president . Romney can lose more votes than he can gain in future debates if he comes across as rude or mean , an impression many had of McCain four years ago . He must stay on the offense . But do n't overdo it .

The opinions expressed in this commentary are solely those of Todd Graham .

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Todd Graham : Romney played to his strengths , Obama to his weaknesses in debate

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He says Romney aced keeping `` smooth '' from turning `` slick ''

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Obama 's lack of passion kept him from connecting with voters ; he missed chances to hit back

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Graham : Obama needs to heat up , pin Romney down ; Romney must keep aggression in check